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<head><meta charset="utf-8"><title>find mvce in huge codebase · t-compiler/wg-prioritization · Zulip Chat Archive</title></head>
<h2>Stream: <a href="https://rust-lang.github.io/zulip_archive/stream/227806-t-compiler/wg-prioritization/index.html">t-compiler/wg-prioritization</a></h2>
<h3>Topic: <a href="https://rust-lang.github.io/zulip_archive/stream/227806-t-compiler/wg-prioritization/topic/find.20mvce.20in.20huge.20codebase.html">find mvce in huge codebase</a></h3>

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<a name="212662965"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/227806-t-compiler/wg-prioritization/topic/find%20mvce%20in%20huge%20codebase/near/212662965" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Stu <a href="https://rust-lang.github.io/zulip_archive/stream/227806-t-compiler/wg-prioritization/topic/find.20mvce.20in.20huge.20codebase.html#212662965">(Oct 08 2020 at 09:00)</a>:</h4>
<p>Yesterday I wanted to find a mvce for <a href="https://github.com/rust-lang/rust/issues/77653">#77653</a> but I had no idea on how to start find the actual bug since there are thousands of tests and lines of code. Is there any way to get some more context about the ICE? I’m fine with compiling rustc from source.</p>



<a name="212664472"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/227806-t-compiler/wg-prioritization/topic/find%20mvce%20in%20huge%20codebase/near/212664472" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> apiraino <a href="https://rust-lang.github.io/zulip_archive/stream/227806-t-compiler/wg-prioritization/topic/find.20mvce.20in.20huge.20codebase.html#212664472">(Oct 08 2020 at 09:16)</a>:</h4>
<p>In this specific case, would the <a href="https://github.com/rust-lang/rust/issues/77638#issuecomment-705105714">playground link</a> (from the linked issue) help finding the regression in rustc?</p>



<a name="212665202"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/227806-t-compiler/wg-prioritization/topic/find%20mvce%20in%20huge%20codebase/near/212665202" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Stu <a href="https://rust-lang.github.io/zulip_archive/stream/227806-t-compiler/wg-prioritization/topic/find.20mvce.20in.20huge.20codebase.html#212665202">(Oct 08 2020 at 09:24)</a>:</h4>
<p>It would not verify that the issue is the same as the substrate one because you would still have to compare any test with the playground to find similarities</p>



<a name="212666499"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/227806-t-compiler/wg-prioritization/topic/find%20mvce%20in%20huge%20codebase/near/212666499" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> apiraino <a href="https://rust-lang.github.io/zulip_archive/stream/227806-t-compiler/wg-prioritization/topic/find.20mvce.20in.20huge.20codebase.html#212666499">(Oct 08 2020 at 09:36)</a>:</h4>
<p>you're right. I thought one could bisect rustc using that playground code -&gt; find a possible culprit commit -&gt; run the Substrate code around that rustc commit and see when it starts failing.But didn't try compiling their Substrate, so I don't know how complex that would be.<br>
I guess then the reporter (from Parity) could perhaps help reducing to a more manageable example</p>



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<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/227806-t-compiler/wg-prioritization/topic/find%20mvce%20in%20huge%20codebase/near/212666934" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Stu <a href="https://rust-lang.github.io/zulip_archive/stream/227806-t-compiler/wg-prioritization/topic/find.20mvce.20in.20huge.20codebase.html#212666934">(Oct 08 2020 at 09:40)</a>:</h4>
<p>Yea probably. I can try the regressed version to check if it’s regressed in the same commit. (But it will still take some time to compile 1300 crates 😅)</p>



<a name="212667528"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/227806-t-compiler/wg-prioritization/topic/find%20mvce%20in%20huge%20codebase/near/212667528" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Stu <a href="https://rust-lang.github.io/zulip_archive/stream/227806-t-compiler/wg-prioritization/topic/find.20mvce.20in.20huge.20codebase.html#212667528">(Oct 08 2020 at 09:47)</a>:</h4>
<p>But it would still be nice to find the case in substrate</p>



<hr><p>Last updated: Aug 07 2021 at 22:04 UTC</p>
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